Parameter monitoring systems can be incorporated with downhole components as fiber-optic distributed sensing systems (DSS). Examples of DSS techniques include Optical Frequency Domain Reflectometry (OFDR), which includes interrogating an optical fiber sensor with an optical signal to generate reflected signals in the optical fiber sensor.
Many downhole applications typically require measuring parameters at extremely long depths, which are further extended in marine applications. Lead-in lengths (i.e., the length of the optical fiber from an optical interrogator to the region of interest) can thus be quite long, which can reduce the effective measurement range of DSS systems.